The successful manufacture of tightly packed semiconductor products depends on obtaining low particle counts on silicon wafer surfaces after rinsing. Heat drying and spin dryers may leave water marks and residue as the water evaporates. Modutek’s advanced IPA vapor dryers use the Marangoni drying effect to reduce particle counts to a minimum. The compact dryer unit can be integrated into wet processing equipment as needed. Modutek’s IPA vapor dryers can increase yields and improve output quality based on reduced particle counts compared to other drying methods.
How the IPA Vapor Dryer Works
In Modutek’s IPA Vapor dryer, an even vapor distribution is ensured by introducing the IPA vapor at the top of the dryer. The vapor is generated in a standard one-gallon bottle located in the exhaust compartment and fitted with a level sensor. Changing the bottle is quick and easy. This arrangement reduces IPA consumption but allows enough vapor to develop the surface tension gradient. As water drains from the bath and runs off the silicon wafer, a small amount of IPA vapor interacts with the thin film of water still coating the wafer. Because IPA has a lower surface tension than water, the surface tension gradient causes the water to flow off the wafer surface. As the water retreats, its flow takes along contaminating particles and other impurities, leaving the wafer completely clean. Because no water is left on the wafer surface, water marks from evaporating water are eliminated.
Advanced Wafer Drying Delivers Many Advantages
The main advantage of using Modutek’s IPA vapor dryer is the reduced particle count. Spin dryers can add particles from the centrifugal action of the spinning. Also, some water will be left to dry, leaving water marks. The Marangoni drying effect utilized in the IPA Vapor Dryer significantly improves wafer cleanliness. Other advantages of Modutek’s dryer include compact installation, low IPA use, and a simple design with no moving parts. The dryer design is flexible enough so that it can be integrated into wet processing equipment. The dryer function can use the same tank as rinsing to save space with a single cabinet. Since the wafers don’t spin, there is no risk of breakage, and a typical drying cycle is completed in ten to fifteen minutes.
The Use of Modutek’s IPA Dryer Can Provide Substantial Benefits
A semiconductor manufacturer can reap substantial benefits when Modutek’s IPA vapor dryer is integrated into wet processing equipment. These include the following:
- Higher throughput due to faster drying times
- Higher yields due to fewer defects from contaminating particles
- Lower costs because of low IPA consumption
- Reduced space due to compact cabinet construction and integration with rinsing
- No IPA heating required
- Flexibility due to multiple drying recipes
- Easy operation with PLC and touchscreen
- Safe operation with safety interlocks, auto lid, and PVC side shields
- Interface capable of working with robotics in wet bench
- No breakage from spinning because there are no moving parts
Additional Features for Specific Applications
In addition to the direct benefits listed above, Modutek’s dryer can be adapted to specific wet process applications. Possible options include an ozone feature that introduces ozone into the cabinet, a quick dump feature, a static eliminator, data logging, and fire suppression. The dryer can handle all wafer sizes and most glass substrates.
Modutek Provides Solutions to Meet Customer Needs
Modutek understands wet-process semiconductor manufacturing and has the in-house expertise to find the best solutions. When working with customers, Modutek can evaluate customer needs and make specific proposals from their complete line of wet-processing equipment. After delivery and installation, Modutek provides unparalleled support to ensure the equipment continues to meet customer expectations.